One of the drawbacks with using video surveillance to monitor a location is that it can be difficult to determine where there are coverage gaps in the surveillance. This difficulty is exacerbated when reconciling surveillance coverage from multiple viewpoints (i.e., when several video cameras are used to cover an area from multiple locations).
The video cameras in a typical security system are usually placed such that all of the scenes which are viewed by the cameras overlap to some extent. However, there are often areas where one or more obstacles block a portion of the field of view of one camera and the remaining cameras are unable to provide adequate surveillance of the blocked area. These gaps in the video surveillance may not be readily apparent when camera data is viewed by security personnel.
One method that is used to minimize the size and number of blocked video coverage areas is to place surveillance cameras at optimal locations such that the effect of obstacles is minimized. The placement of cameras in these desired positions can often be problematic because there may be no infrastructure or supporting structures that exist at these locations making it difficult and/or expensive to adequately mount the video cameras. In addition, even if special arrangements are made to place cameras at these locations, there are typically unforeseen areas of blocked coverage.
Another of the current methods that is used to minimize the size and number of blocked video coverage areas is to place multiple cameras in an area and use rotating field of views for each of the cameras. One of the shortcomings associated with using rotating field of views for each of the cameras is that events in the field of view of the camera can transpire when the camera is not pointing where the events occur. Security personal monitoring multiple screens, and particularly screens with rotating fields of view, frequently fail to detect activity on those screens. In addition, even when rotating field of views are used for each of the cameras, there are typically unforeseen areas of blocked coverage.